1. Technical Field
The present invention relates to an ink composition, an ink jet recording apparatus using the same, and a recorded article produced with the same.
2. Related Art
An inkjet recording apparatus including an ink jet recording head having nozzles from which very small ink droplets are discharged to record information with images and characters is used typically for recording on the surface of ink-absorbent recording media, such as paper. Typically, the ink composition used for the inkjet recording apparatus contains a coloring material such as dye or pigment, and the coloring material is dissolved or dispersed in a mixture of a high boiling point organic solvent and water. The high boiling point organic solvent, which is less volatile and can retain water, helps prevent the nozzles of the ink jet recording head from drying.
On the other hand, ink compositions are desired which allow inkjet recording apparatuses to record information on ink-non-absorbent or ink-low-absorbent recording media, such as book printing paper, synthetic paper, and plastic films, as well as on paper or other ink-absorbent recording media. For example, JP-A-2007-217671, JP-A-2008-101192, JP-A-2009-67909 and JP-A-2010-7054 propose ink compositions that can be used for recording on ink-non-absorbent or ink-low-absorbent recording media.
These ink compositions are, however, unlikely to dry quickly when being applied on an ink-non-absorbent or ink-low-absorbent recording medium because of the presence of a high boiling point organic solvent, such as glycerin. Consequently, the rub fastness of the images or characters of the recorded information tends to be reduced, and the images or characters are liable to be non-uniform in density in a portion formed with a large amount of ink, such as a solid portion.
On the other hand, ink compositions not containing a high boiling point organic solvent do not help prevent nozzles of the ink jet recording head from drying, and consequently, the nozzles are liable to be clogged. In addition, since an organic solvent less soluble in the main solvent is likely to separate from the ink composition, the storage stability of such an ink composition tends to be low.